Wash, pare, and slice the potatoes in 1/4-inch pieces. Slightly grease an earthen or enameled baking dish. Cover the bottom of the dish with a layer of the slices, sprinkle the slices lightly with flour, and put on two teaspoonfuls of butter, or butterine, in small bits. Continue until the dish is nearly full. Pour in milk to barely cover the potatoes, put a cover on the dish and set the dish in an oven of 380° F. Remove the cover in time to allow the top to brown. Allow rather more than half an hour for the baking.